Getting string value from Text field: my 2.5 code stopped working

[Ruslan Zasukhin]

On 5/14/08 8:44 PM, "Matthew Jew" <mjew at icnc.com> wrote:

Hi Matthew, 
 
> (This is another version 2.5.8 to 3.5.2 issue).
> 
> I have for years been using this code to retrieve my long text values
> from my TextFields:
> 
> I_FldBlob_Ptr pBlobField = dynamic_cast< I_FldBlob* >
> (aHTMLTemplateTable->valueText.get());

> dataLength = pBlobField->get_DataSize();
> aMutableData = [[NSMutableData alloc] initWithLength:dataLength];
> 
> Const_I_Value_Ptr myStringValue = aHTMLTemplateTable->valueText-
>> get_Value();
> unsigned long myStringLength = myStringValue->get_Length();
> myStringValue->get_String( (unichar *) [aMutableData mutableBytes],
> dataLength );
> 
> returnValue = [NSString stringWithCharacters: (const unichar *)
> [aMutableData mutableBytes] length:myStringLength ];
> 
> 
> Although this compiles, now my application gets a EXC_BAD_ACCESS
> error on the get_DataSize() call.
> 
> Is there a new way to do this?

Please try this line

 I_FldBlob_Ptr pBlobField = QI( aHTMLTemplateTable->valueText, I_FldBlob );


QI is short cut for QueryInterface(), method good known in the COM.

This is kind of dynamic_cast<>, but based on COM mechanims.
We do not use try COM, we use its ideas


-- 
Best regards,

Ruslan Zasukhin
VP Engineering and New Technology
Paradigma Software, Inc

Valentina - Joining Worlds of Information
http://www.paradigmasoft.com

[I feel the need: the need for speed]